Method of constructing pneumatic tires.



F. S. DICKINSON.

METHOD 0F CONSTRUCTING PNEUMATIC TIRES.

APPLICATION FILED AUG. l. 1918.

1,294,063.` Pated Feb.11,1919.

' 2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

FBEDRICK S. DICKINSON, 0F NEW YORK, N Y.

METHOD 0F CONSTUCTING- PNEUMATIC TIRES.

Specification of Letters Patent.

Original application led February 26, 1915, Serial No. 10,667. Dividedand this application filed August 1, 1918. Serial No. 247,718.

To all whom it ma concer/n.'

Be it known t at I, FREDRICK S. Drex- INsoN, a citizen of the UnitedStates, and resident of New York, in the county and State of New York,have invented certain new and useful Improvements in Methods ofConstructing Pneumatic Tires of which the following is a specification,the subjectmatter of this application being a division from my previouspending application, Serial No. 10,667, filed February 26, 1915.

This invention relates to methods of constructing pneumatic tires suchas are now commonly used upon automobiles and other-` `.therebymaterially weakens the fabric, and

vehicles and which comprise an elastic shoe or casing which constitutesthe outer portion and tread of the tire and incloses the inner air tubeand which has an internal textile body fabric or carcass.

My improvements have particular relation to that class of such tireshoes or casings in which the internal body fabric is of the cord typeand made up of cords or threads laid to cover the circumferential areaof the shoe or casing, in contradistnction to woven fabrics.

In the usual method of constructing such cord or thread body fabrics forthe shoes or casings of pneumatic tires, as now ally employed, the cordsor threa s are hunched, piled, crowded, packed and distorted at theportion of the body fabric which extends at the sides and rim edges ofthe shoe or casing,which conditions arise from the necessity ofequalizing or compensating for the progressive variable difference inthe circumference of the shoe or casing at all points of its areabetween the -ed at the rim bead and the tread or perip ery. The packingand distortion of the cords or threads, as just mentioned, to compensatefor the diferential circumference, not only fractures and weakens theiibers of which the cords or threads-are composed but precludes thatuniformity of tension which is requisite to durability in the life orservice conditions of the tire.

Heretofore, in some methods of constructing the so-called cord tires ofthe class to which my improvements relate, the diferential circumferencehas been equalized or compensated for by attening the cords or threadsand laying up the narrow edges of the cords, which are thus-produced,against or at right angles to the core'or mandrel on ualize or laid overthe core or man which the cord fabric is formed, at that portion thereofwhich corresponds to the side edge or rim bead of the tire, from whichpoint the flattened cords are adually twisted until the .wide or fiatSiriar thereof lays against or parallel to that portion of the core ormandrel which corresponds to the eriphery or tread portion of the tire.Whi e this method of construction compensates for the variablecircumference, in that it serves to extend over or cover the fullvariable circumferential area of the tire shoe or casing, the flatteninof the cords or threads fractures the bers thereof and the twisting notonly precludes the maintenance of uniformity of tension throughout thelength of the c'ords or threads but it creates frictional action betweenthe cords by displacing the position of the twist when the tire isdepressed or flexed in service.

The object of my improved method of constructing the casings ofpneumatic tires is to effectively overcome the conditions andobjectionable features above set forth and produce an improved tire ofthe cord type in which the body fabric will retain all t e initialstrength of the fibers from which the cords or threads are made u andwill insure the requisite uniformity o tension.

In the drawings- Figure 1 is a perspective view, partly in section, of asingle-ply construction of the cord body fabric according to my improvedmethod. v

Fi 2 is a cross-section of the core or man rel over which the cords orthreads are laid in constructing the fabric according to my improved metod, and illustrating the positional relationship of the c ordsthereto.Fi 3 is a detail cross-section illustrating t e single-ply fabricproduced by my im roved method, in its contour as 1t would be 1n alinishedtire under iniiation. Fig. 4 is a plan view illustratm theositional relationship of the cords or s as drel on which the fabric isformed.

Fig. 5 is a perspective view, partly in section, illustrating acompleted tire shoe or casing constructedV according to my rmprovedmethod and showing a construction thereof in which superimposed plies ofthe cod body fabric are employed.

Fig. 6 is a plan view corresponding to Fig. 4 and illustrating amodified construction according to my limproved method, in which a tapemade up of a group of cords or' threads is employed and laid in lieu ofa a single cord.

Fig. 7 is a detail cross-section on the line aio-m, Fig. 6.

Corresponding parts in all the figures are denoted by the same referencecharacters.

Referring to the drawings, 1 designates the tire shoe or casing, whichcom rises the internal fabric body, 2, and the e astic external portionconstituting the tread, 3, which casing incloses the usual air tube andis held in connection with the wheel rim in the usual manner.

The improved cord body fabric, as constructed according to my improvedmethod, is constituted by the cords or threads, 4, which are laid toextend over or cover the entire circumferential area of the shoe orcasing, the construction being preferably roduced by the laying of acontinuous liingth of cord' or thread. Any suitable fiber material ma beemployed for the cords or threads, ut they are preferably composed ofnon-extensible yarns, for instance, combed sea-island cotton spun andvtwisted in non-extensible yarns of suitable or adapted diameter.

In the method of constructing the body fabric 2, as comprised in mypresent invention, the cordsor threads 4 are turned or looped, as at 5,at the terminal side edges or rim-bead portion of the tire, and at saidloops they are laid directly over each other, as at 6, from which ointthey are spread or diverged or radiated in a gradual and continuouspositional relationship, as at 7, at the circumferential side portionsofthe tire,

" so that,they` relatively spread and the under .the full area o cordgradually emerges fromy beneath the upper cord, untilthey extend over orcover the full area of thegreatest circumference of the tire at thetread or peripheral rtion thereof, as at 8. The cord body fa ric, underthe improved method oficonstruction above described thus extends over orcovers f the va ing or differential circumference of tlie tire shoe orcasing, without packing or distortion o r attenin or twisting of thecords oi-v threads, and equalizes orA compensates for the differentialcircumference at all points thereof. It will be noted that the laying uof the cords or threads is preferably suc that the extend on a linediagonal or at an nb ique angle to the transverse or segmentalcrosssectional: lane of the tire. (see Fi 4). In a cord bo y fabric emloyingsiiig e cords or threads, asconstruc accordin to my improvedmethod, the adually iverging or radiating cords 4have a position closelyside by side at that portion of the fabric which is at the point ofgreatest circumference of constructing the tire, which is where thecords cross the tread portion of periphery, as shown inL Fi 4. i

n carrying out the im roved method of the cord bo y fabric, accordin tomy invention the cords are referab y laid over a suitable core or manrel, 10, of such size and form as to conform to the inner contour of theyfinished tire shoe or casing which core is suitably mounted rotatab yto be advanced in step movements graduated accordin to the diameter ofthe cord or thread use At opposite sides of said mandrel, in one type ofbead-edge anchorage constructionas adapted to my resent improvements,are mounted rings or lipops, 11, which are initially held in position asuitable distance away from the core, as shown in Fig. 2, the relativeposition of said rings and core being such that the cords or threadswhen laid will have a proper length to extend over the periphery of thecore and downwardly at each side thereof a suiiicient distance to permitthe rings 11 and the looped portions 5 of the cords to form the sideedges or bead of the tire shoe ery of the core, as at 7-8 (Fig. 4). The

laying of the cords in the manner just indicated is continued until thefabric corresponding to the entire circumference of the tire shoe orcasing is completed, after which e rings 11 or anchorage members arebrou ht inwardl and set a inst the sides of t e core, an suitably ampedin this position `in which the finished fabric will* conform to thecircumferential annular and se ental cross-sectional contour of theiinis ed shoe 'or casing. If a pluralit of plies lare to be employed inthe body abric, as

shown in Fig. 5, the succeeding lies are laid up in like manner as thatjust escribed, but preferably at an obliqlilie an le or diagonalposition opposite to t at o the'preceding PIM en the desired number ofplies have been laid up in the foregoing manner, an elastic hond iscreated between all the cords or threads hy the application of acaoutchouc filler, this being preferably accom lished b impregnating theentire body f ric wit soluble rubber in a vacuum chamber. There is thusproduced a. homogeneous caoutchouc lll Y A so and fabric carcassconforming to the contour of the finished shoe or casin and comprising acasing of rubber in whlch are embedded reinforcing cords or threads.After completion of the homogeneous cord fabric and caoutchouc carcassor casing, as just described, the latter is placed in association withthe elastic external portion of the shoe or casing, which incloses thebody fabric or carcass and forms the usual cushion and tread 3 of thetire, and the complete shoe or casing thus produced is vulcanized orcured in the customary manner.

In carrying out the improved method of constructing the cord bodyfabric, as comprised in my present invention and improvements, I dol notrestrict myself to any particular mechanism or devices for layin up orforming the improved body fabric w ich is produced by my method, as thismay be accomplished in various ways. For instance, the cords or threadsmay be initially wound or looped over the two rings 11 orl anchoragemembers employed, with the latter positioned a proper distance apart toallow suilicient length of cord extendin between them to form the widthof body fa ric which is to ass at the determined oblique angle from t eedge or bead of one side of the tire to the edge or bead of the otherside; then, into the annular completed ring or hoop of the cord fabricso formed upon the side rings 11 or anchorage members, a sectional coreor mandrel is inserted, with the periphery thereof midway between thetwo side rings 11 or anchorage members, after which said side rings arerelatively turned in opposite directions to lay the cords over the coreat the proper oblique angle in the relative position as hereinbeforedescribed and as shown in Fig. 4, in which the cords overlay each otherat the side bends or loops 5 and gradually diverge or radiate therefromso that the under cord emerges from beneath the upper cord, as at 7,until the cords lay para lel and side by s'r'de, as at 8, over thcareaof the peripheral portion of the core.

My improvements as herein described are not restricted to an particulartype of anchorage means or evioes, nor to any particular method ofproducing the diagonal or oblique la of the cords, as the latter may beaccompli ed in any preferred manner or method of laying. For instance,the cords may be initially llaid directly across from and between theLbead-edge supports or anchorage means in a, plane substantiallytransverse 'to that of the annulus of the tire, and

then the laid cords may be shifted at one or both bead-edge portions tochan e the angle and produce the diagonal or ob ique lay, or one' orboth of the beadfedge supports may be shifted to produce the same effectin the diagonal or oblique lay, or the cords may be 'initially nid insaid diagonal or oblique position. VThe shifting method, either of thecords or bead-edge sup orte, as just referred to, forms no part o mypresent application but is embodied in my original application SerialNo. 10,667, filed Februaryl metallic wire or a textile cord, and they'preferably remain within the` completed fabric, so that they form beadsor retaining rings within the selvage edge of thefabric at the loops(Fig. 5), at the side edges or beads of the shoe or casing, by which thetire is held in position on the Wheel rim.

Under some circumstances of tire construction, accordin to my improvedmethod, a single ply of cor body fabric, as shown in Figs. 1 and 4, mayb`e employed, but under some circumstances a plurality of layers orplies or laminations of the fabric may be employed, as shown in Fig. 5,and where a plurality of plies are employed the respec tive plies arepreferably laid to extend in opposite directions in their diagonal oroblique lines with relation to the segmental cross-section of the shoeor easing, which reverse positions of the plies are best adapted toualize all stresses or strains when the tire 1s depressed or exed inService.

Under some circumstances of construction, according to my improvedmethod, in lieu of la ing a sin le cord or thread (as illustra in Fig.4-, the cord bod fabric may be laid froma tape made up o groups ormultiples of single cords or threads, as in the modification illustratedin Fi 6 and 7. The tape shown at 12, in this met od of construction, islaid in the same manner as the Single cord or thread construction, withthe side loops, 5, extending around the rings or hoops 11 or anchoragemembers, at which point the tapes directly overlie each other and fromwhich point the tapes gradually diverge or radiate,as at 7, so that theunder tape gradually emerges from beneath the upper 'tape and the tapesoverlie and extend over or cover, as at 8, the increased circumferentialarea of the peripheral or tread portion of the shoe or casing. In viewof the increased width of the tape unit, in contradistinction to thesinglecord construction as shown in Fig. 4:, it is not necessary thatthe tapes lay side by side at the lperipheral or treadV ortion, as isthe case with the single cor method of construction, but the tapes arelaid to overla a suitable portion of their respective widt s, as shownat 14, at the peripheral or tread portion, which overlappingconstruction fully e ualizes and compensates for the differentialiameters in the samemanner ing myself to the detail features of thements. I therefore reserve from beneath Y lying position at an method ofconstruction as herein illustrated and described, as it is manifest thatvariations therein may be resorted to in the adaptation of the method ofconstruction to varying conditions according to the type of pneumatictire casing to which the cord body fabric as produced by my method is tobe applied, without departing from the spirit and scope of my inventionand improvethe right to all such variations and modifications asproperly fall within the sco e of 1n and the terms of the fol owing caims.

Having thus described my invention, I claim and desire to secure byLetters Patent:

1. The method of constructing the internal body fabric for the shoe orCasin of pneumatic tires of the cord type, w ich consists in laying alen h of textile cord or thread with turns or oops at an angle to theannulus of the tire at the terminal side edges or rim-bead portionthereof and with the cord laid over itself at said turns or loops andspread or diverged from said looped portion in a gradual and continuousrelationship at the circumferential side portions of the tire so thatthe under portion of the length of cord gradually emerges the upperportion thereof and said under and upper portions relatively spread andextend over the enlarged circumferential area and conj ointly cover thespace area of the greatest circumference of the tire at the tread orperipheral portion thereof, to equalize or com ensate for theprogressive variable circum erence of the tire and entirely cover thesame by said length of cord itself without distortion or {iattening ortwisting of the textile cord.

2. The method of constructing the internal body fabric for the shoe orcasin of pneumatic tires of the cord type, w 'ch consists in laying thecords or threads of which the body fabric is com osed in overangle tolie annulus of the tire at the terminal side edges or rimbead portionthereof and with the cords relatively spread or diverged from saidoverlying position at the side-edge portion of the tire in a gradual andcontinuous positional relationship1 at the circumferential side portionsof e tire so that the under invention length of cord gradually emergesfrom beneath the upper length and said under and upper lengthsrelativelys read and extend over the enlarged circum erential area and conjointlycover the space area of the greatest circumference of the tire at thetread or peripheral portion thereof, `to equalize or compensate for theprogressive variable circumference of the tire and entirely cover thesamel by the spread of said length of cords from their side-edgeposition at an angle to the' annulus of the tire Without distortion orflattening or twisting of the cords.

c3. The method of constructing the internal body fabric for the shoe orcasing of pneumatic tires of the cord type, which consists in laying thecords or threads of which the body fabric is composed in a singlethickness or ply with portions relatively spread or diverged andemerging one from beneath the other at the circumferential side portionsof the tire to the tread or peripheral portion thereof in a gradual andcontinuous positional relationship so that said portions relativelyspread and extend over Athe enlarged circumferential area and conjointlycover the space area of the progressive variable circumference of thetire at the tread or peripheral portion thereof, to equalize orcompensate for the prosive variable circumference of the tire andentirely cover the same by the spreading and divergent cords of saidsingle thickness or ply without distortion or flattening or twisting ofthe cords.

4. The method nal body fabric for the shoe or casing of pneumatic tiresof the cord type, which consists in layin the cords or threads of whichthe body abric is composed in overlying position at an angle to theannulus of the tire at the terminal side edges or rim-bead portionthereof and with the cords relatively spread or diverged from saidoverlying pos'tion at the side-edge portion of the tire in a gradual andcontinuous positional relationship at the circumferential side portionsof the tire and extending side by side in abutting position at theperipheral or tread portion thereof so that the under length of cordgradually emerges from beneath the upper length and said under and upperlengths relatively s read and extend over the enlarged circum erentialarea and conj ointly cover the space area of the greatest circumferenceof the tire at the tread or peripheral ortion thereof, to equalize orcompensate or the progressive variable circumference of the tire andentirely cover the same by said spreadin and abutting cords withoutdistortion or attening or twisting of the cords.

5. The method of constructing the internal body fabric for the shoe orcasing of of constructing the interpneumatic tiresy of the cord type,which consists in laying a plurality of layers or plies respectivelycomprisin cords or threads laid in overlying osition at an angle to theannulus of the tire at the terminal side edges or rim-bead portionthereof and with the cords relatively spread of diverged from saidoverlying position at the sideedge portion of the tire in a gradual andcontinuous positional relationship at the circumferential side portionsof the tire so that in each respective layer the divergent portions of'the lengths of cord relatively s read and extend over the enlargedcircum erential area to conjointly and entirely cover the space area ofthe rogressive'variable circumference of the tire without distortion orflattening or twisting of the cords.

6. The method of constructing the internal body fabric for the shoe orcasin of pneumatic tires of the cord type, which consists in anchoringthe cords or threads of which the bod fabric is composed at the terminalside e ges of the tire and laying the cords in engagement with theanchoring means in overlying position at an angle to the annulus of thetire and with the cords spread or diverged from said overlying positionin a gradual positional relationship at the circumferential sideportions of the tire so that the under length of cord gradually emergesfrom beneath the upper length and said under and upper lengthsrelatively spread and extend over the enlarged circumferential area andconjointly cover the space area of the greatest circumference of thetire at the tread or peripheral portion thereof, to equalize orcompensate for the progressive variable circumference of the tire andentirely cover the same by the spread of said length of cords from theirside-edge position at an angle to the annulus of the tire withoutdistortion or flattening or twisting of the cords.

7 The method of constructing the internal body fabric for the shoe orcasing of pneumatic tires of the cord type, which consists in anchorinthe cords or threads of which the body fa ric is composed at theterminal sideedges of the tire and layin the cords with loops or turnsenging sai anchoring means at an angle to e annulus of the tire and withthe cords extending over each other at said looped ortions an spread ordiverged therefrom in a gradual and continuous positional relationshipat the circumferential side portions of the tire so that the under cordsgraduall emerge from beneath the upper cords an the under and upperlengths from said loops re1- atively spread and extend over the enlargedcircumferential area and conjointly cover the space area of the greatestcircumference of the tire at the tread or peripheral portion thereof, toequalize' or compensate for the progressive variable circumference ofthe tire and entirely cover the same by the spread of said length ofcords from their loo at an angle to the annulus of the tire wi outdistortion or flattening or twisting of the cords.

B. The method of making a hollow annular cord web, which compriseslaying cord onto supports of different diameters .to form two series ofcord elements, the cord being so arranged that the cord elements of oneseries lie between the cord elements of the other series at theperiphery of the annular cord web but not at the sides of said web.

9. The method of constructing the internal body fabric for the shoe orcasin of pneumatic tires of the cord type, w ich consists in laying cordonto a mandrel or former of one diameter and on bead-edge anchorages oflesser diameter, to form two series of cord elements and in suchposition that the cord elements of one series overlie the cord elementsof the other series at an angle to the annulus of the tire at therimbead portion, and spreadin or diverging said cord elements from saioverlying osition in a gradual positional relations ip in which theundercord elements of one series emerge from beneath the outer cord elementsof the other series at the circumferential side portions of the tire andthe space area at the tread or peripheral portion of the tire is coveredconjointly by the cord elements of both series, to equalize orcompensate for and cover the progressive variable circumference of thetire.

In testimony whereof I have signed the foregoing s eclication.

F EDRICKS. DICKINSON.

